Re: [PATCH 2/2] services: postgresql: Add locale to configuration

[Christopher Baines <mail@cbaines.net>]

On 11/12/16 23:14, Ludovic Courtès wrote:
> Hi!
>
> Christopher Baines <mail@cbaines.net> skribis:
>
>> * gnu/services/postgresql.scm (<postgresql-configuration>): Add locale
>>   field.
>>   (postgresql-shepherd-service): Pass locale to initdb.
>>   (postgresql-service): Add locale default.
>
> [...]
>
>> +  (locale         postgresql-configuration-locale
>> +                  (default "en_US.UTF-8"))
>
> Note: this should use the “normalized codeset”, so “en_US.utf8”.
>
>>           (let ((user (getpwnam "postgres"))
>> -               (initdb (string-append #$postgresql "/bin/initdb")))
>> +               (initdb (string-append #$postgresql "/bin/initdb"))
>> +               (initdb-args
>> +                (append
>> +                 (if #$locale
>> +                     (list (string-append "--locale=" #$locale))
>> +                     '()))))
>>             ;; Create db state directory.
>>             (mkdir-p #$data-directory)
>>             (chown #$data-directory (passwd:uid user) (passwd:gid user))
>> @@ -103,14 +110,19 @@ host	all	all	::1/128 	trust"))
>>                  (lambda ()
>>                    (setgid (passwd:gid user))
>>                    (setuid (passwd:uid user))
>> -                  (primitive-exit (system* initdb "-D" #$data-directory)))
>> +                  (primitive-exit
>> +                   (apply system*
>> +                          initdb
>> +                          "-D"
>> +                          #$data-directory
>> +                          initdb-args)))
>>                  (lambda ()
>>                    (primitive-exit 1))))
>>               (pid (waitpid pid))))))))
>
> The effect of that is that ‘initdb’, but not ‘postgresql’ itself, would
> run in a locale different from the system locale by default.
>
> These two inconsistencies may be quite confusing.  WDYT?

I believe the locale passed to initdb sets "the default locale for the 
database cluster", so I'd imagine that there is no problems with running 
PostgreSQL (it seems to work for me). I think its good to support 
setting it explicitly, but it would also be good to use the system 
locale as a default.

I thought about trying to get the LANG from /etc/environment, or the 
<operating-system>, but I could not see an easy and elegant way to do 
either. By default, initdb will use the environment, its just that the 
environment during service activation contains no locale information.